1. Field of Invention
The present invention relates to oxygen activation nuclear well logging.
2. Description of the Prior Art
Prior U.S. Pat. No. 3,465,151 discloses a technique for oxygen activation nuclear well logging of formations adjacent a well borehole. Although it is mentioned and recognized in this prior U.S. patent that the presence of water and, thus, oxygen in the well borehole will tend to obscure radiation of interest from the formations, no effort is made to compensate for this presence. In fact, it is indicated that the methods of this prior U.S. patent have greatest utility in empty or oil filled boreholes. However, typical boreholes contain some measure of water. Another factor known to be often present but not compensated for was variations in the flux intensity of the neutrons on the oxygen activation readings.